1. Field of Invention
The present invention relates to a multi-level voltage detection circuit. More particularly, the present invention relates to a multi-level voltage detection circuit of a mother board.
2. Description of Related Art
The power supply unit starts a self-testing process while the computer starts. When the current volume and the signal voltage reach a pre-determined level, the power supply unit issues a power good signal to acknowledge the mother board. The microprocessor keeps resetting until the timing control unit of the microprocessor receives the power good signal.
The conventional power supply unit usually provides a power signal of only one voltage level, and the mother board is acknowledged when the power signal has reached that voltage level. However, the motherboard cannot tell weather the power signal has reached the desired voltage when the power supply unit provides a power signal of more then one voltage level.
For the forgoing reasons, there is a need for a new detection circuit which can acknowledge the mother board that the power signal has reached the desired voltage level while the power supply provides multi-level voltages.